A video uploaded to YouTube shows the great white in the water right next to the boat as people can be heard shrieking excitedly in the background.

The shark, whose size was estimated at anywhere between 3.5 and six metres long, may well have been staking out its dinner, researcher Steve Campana told CBC News.

"A typical shark is really only driven by a couple of things; one is sex and one is food," he said.

"In this case, there’s no indication it was mating. It was probably cruising around in appropriate water temperatures to look for food. ... It was probably just exploring."

There may be thousands of these sharks swimming near Canadian shores after their numbers grew by an estimated 10 to 20 per cent in the Atlantic Ocean over the past 10 years. But Campana said people have nothing to be scared of.

"Nobody has been bitten by a shark of any kind in Canadian waters," he said. "These whites are not particularly interested in people."